p21WAF1/CIP1 expression is a marker of poor prognosis in oral squamous cell carcinoma

Abstract

Background: Previous research on the prognostic relevance of p21(WAF1/CIP1) in oral squamous cell carcinomas (OSCC) yielded inconclusive and contradictory data.

Objectives: To investigate the prognostic significance of p21(WAF1/CIP1) expression, its relationship to p53 accumulation, proliferation-associated proteins Ki-67 and cyclin D1 in relation to survival and clinicopathological features in OSCC.

Methods: Surgical specimens taken from 106 randomly selected patients were studied by immunohistochemistry. Expression of the protein of interest was correlated with clinical data.

Results: p21(WAF1/CIP1) expression was found in 61.3% of OSCCs. Expression of p21(WAF1/CIP1) significantly correlated with tumor size (P = 0.005), lymph node involvement (P = 0.002), clinical stage (P < 0.001), and tumor site (P = 0.002). Patients with tumors showing p21(WAF1/CIP1) immunopositivity had decreased 2-year survival (P = 0.018). Expression of p21(WAF1/CIP1) was not related to age, gender, risk factors (tobacco, alcohol), dental status, or tumor differentiation grade. The p21(WAF1/CIP1) expression positively correlated with proliferation-related variables Ki-67 (P = 0.010) and cyclin D1 (P < 0.001), but not with p53 expression.

Conclusions: The expression of p21(WAF1/CIP1) was found to be associated with poorer prognosis and tumor aggressivity in OSCC.